Ethers of cashew nut sheell liquid and process of making them



Patented Apr. 29, 1941 ETHERS OF CASHEW NUT SHELL LIQUID AND PROCESS OF MAKING THEM Solomon Caplan, New York, N. Y., assignor to The a corporation or New Harvei Corporation,

Jersey No Drawing. Application May 19, 1937, Serial No. 143,495

13 Claims. (Cl. 260-521) The present invention relates to methods and steps of transforming cashew nut shell liquid by the substitution of hydrocarbon radicle for the hydrogen of the phenolic hydroxyl groups characteristic oi the constituents of cashew nut shell liquid, which are principally cardol and anacardic acid, and the present invention relates also to the ethers which are the transformation products oi the methods of the present invention and to cashew nut shell liquid in which a substantial part or all of said hydrogen is replaced by a hydrocarbon radicle.

The primary hydrocarbon ethers are the most stable under heat; the secondary hydrocarbon ethers are next in stability; and the tertiary hydrocarbon ethers are, least stable, and even unstable. changing to the corresponding substituted phenols.

An object of the present invention is to provide hydrocarbon ethers of phenols, which ethers have a degree of stability when subjected to heat.

Cashew nut shell liquid is composed substantially entirely of a mixture of cardoi and anacardic acid each of which compounds has a long chain unsaturated hydrocarbon substituents on the nucleus and a hydroxyl group on the nucleus. and it is an object of the present invention to substitute a hydrocarbon radicle for the hydrogen of said hydroxyl groups, either to completion or to a substantial degree.

Either raw cashew nut shell liquid or cashew nut shell liquid which has been somewhat modi-. fled is suitable for the practice of the present invention to make products for various uses. For example, cashew nut shell liquid which has been treated by the method of Patent 2,067,919 to Harvey and Damitz and which is in the liquid state can be modified to make ethers according to the present invention by substantially the same steps as used for making ethers of raw cashew nut shell liquid. According to said Patent 2,067,919 cashew nut shell liquid is treated with material such as sulphuric acid to throw out naturally occurring metals as salts which can be separated from the treated cashew nut shell liquid, also this patent describes the further use of the sulphuric acid to polymerize the cashew nut shell liquid to various stages and states among which are liquids which are suitable for the practice of the present invention.

An example of the practice of the method of the present invention together with the product thereof is as follows. 7'

Three thousand pounds of cashew nut shell liquid and about 1060 pounds oi primary amyl chloride are placed in a tank having a steam jacket; a circulating pipe line loop from the bottom thereof, through a pump and then back to the upper part of said tank; and a pressure tight cover. About four hundred and fifty pounds of sodium hydroxide are dissolved in about two hundred and sixty gallons of water and the solution added to the ingredients in the tank.

- The cover is then closed and tightened and the materials in the tank, by means 01' said pump, are looped through said pipe line for thorough mixing. By means of said steam jacket, the temperature is brought up to about 325 F. and maintained there for about seven hours, the pressure in the tank accordingly being at to lbs. At the end of this time the steam is cut oil. the water jacket, the pump is stopped and the tank is left to cool over night at which time the temperature has dropped to about 250 F. to 275 and the pressureto about 40 lbs. and the water solution of sodium chloride and any unreacted sodium hydroxide has settled to the bottom of the tank. The pressure is relieved and the salt solution drawn oil, after which the cashew nut shell liquid-amyl ether reaction product is tested and neutralized for any alkalinity or acidity. A satisfactory condition for many purposes is slightly acid to methyl orange or phenyl red. The cashew-amyl other can then be heated to about 260 F. to drive off any water therein.

In like manner the ethyl ether of cashew nut shell liquid can be made by using ethyl chloride instead of the amyl chloride, the amount oi ethyl chloride used being molecularly proportional to the amount of amyl chloride used in the previous example. Likewise benzyl chloride and naphthyl chloride can be used for making the corresponding ethers.

Monohydrocarbon and dihydrocarbon sulphate can also be used, in the presence of alkali, to produce hydrocarbon ethers of cashew nut shell liquid. Either dry, powdered alkali or solution, as in water, can be used. However when the al- .kali solution is used heating in a closed container agents suitable for use in making hydrocarbon ethers of cashew nut shell liquid, with the aid of an alkali such as sodium hydroxide, potassium hydroxide, calcium hydroxide, and so on. These reagents are used in amounts to give molecular ratios of the hydrocarbon radicle to cashew nut shell liquid, the molecular weight of the latter being taken as about 288. 1

The products of the'present invention are suitable for various purposes amongwhich is the distillation thereof to obtain the hydrocarbon ethers of the anacardic acid constituent of cashew nut shell liquid, which are described in my copending application Ser. No. 733,986, filed July 6, 1934, now Patent No. 2,181,119, issued November 28,- 1939, and to obtain ether residues. The present method has some advantages, for example the ethyl ethers of cashew nut shell liquid gives a higher yield of the ethers of the anacardic acid constituent by steam distillation than does the method of said copending application and the yield can be as high as 75%] or more.

The distillation of the hydrocarbon ethers of cashew nut shell liquid of thepresent invention can be carried on under vacuum or at atmospheric pressure and can be carriedon with steam. At about 250 to 300 C. the distillation with steam is destructive and the products are the hydrocarbon ethers of cardanol such as described in said copending application.

In the claims the term ethers of the anacardic acid constituent of cashew nut shell liquid is considered to be generic to ethers of anacardic acid and to ethers of cardol.

Certain of the inventions disclosed herein are claimed in my copending application Serial Number 291,706, filed August 24, 1939, which is a. division of the present application.

Having thus describedmy invention, what I claim and desire toprotect by Letters Patent is:

1. The method of treating cashew nut shell liquid which comprises substituting a hydrocarbon group for thehydrogen of the phenolic hydroxyl group of phenolic compounds in the cashew nut shell liquid by bringing cashew nut shell liquid into contact with a caustic alkali and a hydrocarbon ester of a mineral acid.

2. Cashew nut shell liquid which has been transformed by the substitution of a hydrocarbon radical for hydrogen of phenolic hydroxyl groups in cashew nut shell liquid.

3. Cashew nut shell liquid which has been transformed by the substitution of a primary hydrocarbon radicle for hydrogen of phenolic hydroxyl groups in cashew nut shell liquid.

4. Cashew nut shell liquid which has been transformed by the substitution of a primary alkyl hydrocarbon radicle for hydrogen oi phenolic hydroxyl groups in cashew nut shell liquid.

5. Cashew nut shell liquid which has been transformed by the substitution of a primary alkyl hydrocarbon radicle for hydrogen of phenolic hydroxyl groups in cashew nut shell liquid and in. which the hydrocarbon radicle is from the group consisting oi methyl, ethyl and amyl.

6. The method which comprises substituting a hydrocarbon group for the hydrogen 0f the hydroxyl ,group of cashew nut shell liquid by bringing cashew nut shell liquid into contact with a caustic alkali and a hydrocarbon ester of a mineral; acid, and subsequently distilling with steam to obtain the hydrocarbon ethers of the anacardic acid constituent of cashew nut shell liquid and cashew nut shell liquid ether residue.

'7. The method which comprises substituting a primary alkyl group for the hydrogen of the hydroxyl group of cashew nut shell liquid by bringing cashew nut shell liquid into' contact with a caustic alkali and a primary alkyl ester of a mineral acid, and subsequently distilling to obtain the corresponding primary alkyl ether of the anacardic acid constituent of cashew nut shell liquid.

8. The cashew nut shell liquid hydrocarbon ether residue obtained by distilling oil a substantial amount of the hydrocarbon ethers of the anacardic acid' constituent from hydrocarbon ethers of cashew nut shell liquid.

9. The method which comprises bringing cashew nut shell liquid into contact with a hydrocarbon ester of a mineral acid and material selected from the group'consisting of alkali metal hydroxides and alkaline earth metal hydroxides.

10. The method which comprises bringing raw cashew nut shell liquid into cotact with a hydrgcarbon ester of a mineral acid and a caustic a1 11.

11. The method which comprises bringing raw cashew nut shell liquid into contact with a hydrocarbon ester of a mineral acid and a caustic alkali at temperatures between the normal and about 325 F.

12. The reaction product obtained by bringing raw cashew nut shell liquid into contact with a hydrocarbon ester of a mineral acid and a caustic alkali.

13. Cashew nut shell liquid which has been transformed by the substitution of a hydrocarbon radicle for hydrogen of hydroxyl groups in cashew nut shell liquid.

SOLOMON CAPLAN. 

